Guardsman
/ˈɡɑːrdzmən/
Definition 1 of 1
Pro Tip 1/3Specific Role
Refers to soldiers with ceremonial or protective duties, not all military members. 
He became a guardsman, serving at official state ceremonies.
Pro Tip 2/3Royal Association
Often used with royal or palace, signifying a connection to the monarchy. 
The royal guardsman wore a uniform different from the regular army.
Pro Tip 3/3Gender Neutral
Applies to both male and female soldiers; not gender-specific. 
The guardsman standing next to the queen could be either a man or a woman.